Abstracts
2002 Digestive Disease Week

# 102442 Abstract ID: 102442 Long Term Functional Results of Coloanal Anastomosis with Preoperative versus Postoperative Radiotherapy for Rectal Cancer
Daniel R Nathanson, N J Espat, Warren E Enker, Jose G Guillem, Alfred M Cohen, W D Wong, Phillip B Paty, New York, NY

Introduction: Preoperative radiotherapy (RT) for rectal cancer avoids radiation to the reconstructed rectum and may circumvent the detrimental effects on bowel function associated with postoperative RT. We compared the long-term functional results of patients who received preoperative RT, postoperative RT, or no RT in conjunction with low anterior resection (LAR) and coloanal anastomosis (CAA) to assess the impact of pelvic radiation and its sequencing on anorectal function. Methods: One hundred nine patients (75M:34F, age range 24-90 years) treated by LAR and straight CAA for rectal cancer between 1984 and 1997 were assessed with a standardized questionnaire at 2-8 years post resection. All radiotherapy was given to a total dose of 4500-5400cGy using conventional fractions. Results: There were 39 patients in the preoperative RT group, 11 patients in the postoperative RT group, and 59 patients in the no RT group. The postoperative RT group reported a significantly greater number of bowel movements per 24-hour period (p < 0.01) and significantly more episodes of clustered bowel movements (p < 0.05) as compared to either the preoperative RT group or to the no RT group. No significant difference in anal continence or satisfaction with bowel function was found among the three groups. Conclusion: Postoperative pelvic RT has significant adverse effects on anorectal function. Preoperative pelvic RT, however, has no measurable impact. We attribute this difference to the effect of postoperative RT on the neorectum, which is not radiated when treatment is given preoperatively. We believe the deleterious effect of radiation on bowel function can be minimized by its delivery in the preoperative setting